add build and changelog scripts

Author: denco

package.json

@@ -121,6 +121,7 @@
 		}
 	},
 	"scripts": {
+		"build": "npm run package",
 		"vscode:prepublish": "npm run compile",
 		"compile": "tsc -p ./",
 		"watch": "tsc -watch -p ./",
@@ -132,7 +133,8 @@
 		"prepackage": "npm run clean && npm run compile",
 		"package": "vsce package",
 		"clean": "rimraf -rf ./out",
-		"clean-all": "rimraf -f ./confluence-markup*.vsix; rimraf -rf ./.vscode-test; rimraf -rf ./out; rimraf -rf ./node_modules"
+		"clean:all": "rimraf -f ./confluence-markup*.vsix; rimraf -rf ./.vscode-test; rimraf -rf ./out; rimraf -rf ./node_modules",
+		"changelog": "if [ $((grep \"$(grep -m1 'version' package.json | cut -d '\"' -f 4)\" -n CHANGELOG.md || echo 0) | cut -d ':' -f 1) -eq 3 ]; then awk '/##/{++c;next} c==1' CHANGELOG.md | awk '!/^$/'; fi"
 	},
 	"devDependencies": {
 		"@types/glob": "^7.1.1",